Rheostat.



P. H. ZIMMER.

RHEOSTAT.

APPLICATION FILED MAY 20, 1907.

Patented 001;. 20, 1908.

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FigJ.

.lNvENTn FIAUZQZMER. I ATTY.

P. H. ZIMMBR. BH'EOSTAT. APPLICATION FILED MAY 29,1907.

Patented Oct. 20, 1908.

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WITNESSES-- WW 6.8m.-

INVENTDR PAUL HZIMMER,

UNITED STATES Par a PAUL H. ZIMMER; or SOHENEOTADY', NEW YeRK, ASSIGNOB TO GENERAL nrao'i'n e;

' COMPANY, A ooRroaA'rroN QFNEW YORK.

nmosra'r.

Specifleation oi Letters Patent.

Patented Oct. 20, 12%..

application-filed may 20, 15907. Serial amnesia.

To all whom it may concern:

Be it knownthat I; PAUL H. ZIMMER, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certainnew and useful Improvements in Rheostats, of which the following is a specification.

This'invention relates to means for controlling electric circuits and has for its object the provision of a device of this character which will start the motor and regulate the speed thereof in a reliable, safe and ef ficient mamier.

One of the objects of my invention is to provide an improved rheostat by means of which the motor may be broughtup to run illustration. I W e -Inthe drawings, Figure 1 1s a plan view ning speedthrough a starting resistance and the speed then controlled through another resistance, preferably in the motor field cirof the rheostat embodying one form of my invention and showing the arrangement of,

' circuits; Fig. 2 is a view showing the working parts in operative position; Fig. 3 is a plan, view of a modified form of myinven tron; and Fig. 4 is a view show ng the working parts in starting position.

Referring-first to Figs. 1V and 2, is an insulating base of slatev or soap-stone provided with a series of contacts 11 arranged in an arc of a circle and forming the tenninals of the startingresistance12. Contacts 13 forming the terminals of the regulating resistance 15 and contact 14 are arranged concentrally with the studs 11, anda controlling arm 16 pivoted at 17 and provided with an'operating handle 18 is adapted to sweep over and simultaneously engage these contacts. A disk 19 is rotatably mounted upon the pivot 17 so as-to move 'independently of the arm-16. This disk is biased or 'sprin gqiressed to move in a counter-clock wise direction by means of the spring 20, one end of which bears against. the stop 21 while the other end bears against the. pin22 mounted upon thcdisk 19. This pin projects upward from the disk and abuts against the arm 16'so that the arm has a bias in a. counter-clockwise direction so as to normally engage the stop 21. A controlling element or switch lever 23 is pivoted in proximity to the arm 16 at 24 and at its outer end engages contacts 25 and: 26 arranged in an arc of a,

circle of which 24 is the center, andseparated by dead contacts 27. The lever 23 is likewise biased or spring-pressed by means of a spring 28 which normally presses it in a clockwise direction against the stop 29. The lever is extended beyond the pivot so as to form an armature portion 3Q'cooperating' with a no-voltage magnet 31. A projecting portion or shoulder 32 is secured to the arm through conductor 35, field F, conductor 36 to stud 26 thence through thelever' 23 and conductor 37 back to' the negative main. At the same timethe magnet 31- is connected across the line through conductor 38, resist ance R, conductor 39 and conductor 40back to the negative main. As the arm16 is moved towards the right and engages the first ofthe'studs 11, thelarmat-urecircuit is closed as follows; From'the. positive main through armature A,- conductor 41 to stud 25 v thence throughresistance12, arm 16 and conductor 37 back to line. Asxthe arm is moved. farther to the right, the starting re-' sisrance is gradually cut out, the field re sistance being in the meantime short-circui ted- When the arm 16 approaches the the shoulder32and moves the lever 23 into engagement with the retaining magnet so that its outer end rests on the stud 25. The curved portion of the shoulder passes over I the-pin 22 and holds the disk in the position shown"inleig.v 2. The armature resist'anceis now short-circuited, the current passingi'rom stud .25 directly through lever 23 to the. pivot 17 instead of through the resist ance and arm 16. At the same -time' the short-circuit of the field resistance is broken at contact 26 so that the field circuit instead of going from conductor 36 and stud 26 through thelever 23, passes from the con-' ductor 36 at 42 to the 'field resistance 15,

thence through the arm 16 and back to line again in a position for starting. The motor may also be stop ed by moving the arm 16 backward over al of the studs 13 until it bridges thefirst stud 13 and stud l4: lVhen these two studgs are bridged the magnet 31 i's sliort-oircui ed and the parts automatically return to startingposition.

In Figs. 3 and 4 have shown my invention applied to a rheostatinwhich only a single step of resistance is used in the armature circuit. This resistance 12 is cut out by the lever 23 when the latter is moved from stud 48 to stud 25. In this form of my invention when the line circuit is closed the field is energized as follows: From the positive main through conductor 44, lever 23, stud.26 conductor 45, field F, conductor 46 and back to the negative main. As the arm 16 is moved to the right the field resistance 15 is short--circuited but the armature resistance is not closed until the arm 16 approaches the limitof its movement and the element 23 is shifted from stud 26- to stud 43. The direction of the current through the armature is then as tollowsz From the positive main through conductor 44, lever 23; stud 43, starting resistance 12, conductor 4:7, armature A, conductor 46 and back to the negative main. At thesame time the short circuit of the field resistance is broken at '26 in the same manner as in the form shown in Fig. 1. As the arm 16 is moved farther to the right, the lever 2-3 leaves stud l3 and passes on-to stud 25 thereby short-circuiting the starting-resistance 12 -and placing the motor armature directly 'on the line. Upon failure of voltage theparts arereturned to their starting position as before described, and the motor may also be stopped by bridging contact 13 and contact 48 which short-circuits the re-- tective position, it being impossible for the' parts to be operated in any other than the proper way. Various modifications of my invention-will suggest themselves to those skilled in {the art, all of whi' ch come within the spirit"ot. my invention, in so far as thev fall within the scope of the claims annexed hereto.

hat I claim as new and desire to secure by Letters Patent of the United States, is,-'-

l. A rheostat comprising resistance contacts, a controlling arm therefor springpressed towards its initial position, a circuit controlling element independently spring-pressed and arranged to hold the spring pressure from said arm. and a novoltage magnet for retaining the element in a holding position.

2. A rheostat comprising resistance contacts, circuit controlling elements biased to rotate in opposite directions, a no-voltage magnet for retaining one of said elements in a predetermined position, and means whereby the bias is removed from the other element when the said position is reached.

3. A rheostat comprising resistance contacts, a controlling arm biased to rotate in a predetermined direction, a circuit controlling element biased to rotate in an opposite direction, a 'no-voltage magnet for retaining said element in a biased position, and means whereby the bias is removed from the controlling arm when said element reaches the biased position.

4. A rheostat comprising resistance contacts, a controlling arm therefor, a springpressed member arranged to'norinally engige said arm and bias it towards a predetermined position, a circuit controlling elemeht arranged to hold said member out of engagement with said arm, and a no-voltage magnet for retaining said element in a holding position. i

5. A rheostat comprising resistance contacts, a controlling arm biased to rotate in a predetermined direction, a circuit controlling element arranged to be engaged by said arm and rotated in the same direction, means whereby the bias is removed from the controlling arm when said element reaches a predetermined position, and a no-voltage magnet for retaining the element in said position.

6. A rheostat comprising" resistance contacts, a controlling arm biased to rotate towards an initial position, a circuit controlling element biased to rotate in an opposite direction and arranged to be engaged by said arm and moved againstits bias to a prede tacts, a controlling arm spring-pressed to- 1 wards an initial position, a circuit controlling elementspring-pressed m -a n opposite direction towards an initial position and arranged to be engaged'by said arm and moved agamst its spring tension to a second position, means whereby the said element holds the spring tension from the arm when it reaches said second position, and a no-vol-- tage magnet for retaining the element in said gage said arm and bias it towards a predetermind position, a circuit controlling element arranged-to be rotated to a predeter mined position by the movement of thearm, means whereby said e ement engages sa1d member and holds the spring tension from the arm when the element reaches said position, and a no-voltage magnet for retaining the element in a holding position. 9. A rheostat comprisin'g a pairof resistances provided with contacts, a controlling arm simultaneously engaging said contacts -and spring-pressed toward its initial positlon, a circuit controlling element arranged to hold the spring pressure from said arm, anda 'no-voltage magnet for retaining the element in a holding position.

10. -A rheostat comprising a pair'of resist ances provided with contacts, a controlling arm simultaneously engaging said contacts, a springpressed member arranged to normally engage said arm and bias it towards its initial position, a circuit controlling element arranged to hold said member out of engagement with said' arm and-a no-voltage magnet for retaining said element in a holding position.

11. Asta'rting rheostat comprising a starting resistance and, a field resistance each provided with contacts, a controlling arm simultaneously engaging said contacts and spring-pressed towards its starting position, a circuit controlling element arranged to hold the spring pressure from said arm,-'and a novoltage magnet for retaining the element in a holding position.

12, A starting rheostat comprisinga start-- ing resistance and a field resistance each provided with contacts, a controlling arm simultaneously engaging said contact-s, a spring-pressed member arranged tonormally engage said arm and bias it towards the start-.

ing pos1tion,-a circuit controlling element arranged to hold Said member'out of en'- gagement with said arm, and a no-voltage magnet. for retaining said element in a hold-- ing position.

13. A starting rheostat comprising a starting resistance and a field resistance each provided with contacts, a controlling arm simultaneously engaging said contacts and spring-pressed towards the starting position, a circuit controlling element arranged to be engaged by said arm when the latter is.

moved to running position and be moved thereby to a predetermined position, means whereby 'the element holds the spring pres sure from the arm when the element reaches v said position, and a no-voltage magnet for retaining the element in a holding position.

let. A starting rheostat comprising'a starting resistance and a field resistance eacl" provided with contacts, a controlling arm simultaneously engaging said contacts, a spring-pressed member arranged to normally engage said arm and bias it towards a predetermined position, a circuit controlling element arranged to be moved to a predetermined position by. said arm, means whereby said element engages and holds said mem her when the element reaches said position, and a no-voltage magnet for retaining said element in a holding position.

15. A starting rheostat comprising a starting and a field resistance each provided with contacts, a controlling arm simultaneously engaging said contacts, a spring-pressed member'arranged to normally engage said arm and bias it towards its starting position, a circuit controlling element spring-pressed inanopposite direction towards its initial position andarranged to be moved: to a predetermined position by the movement of said arm, means whereby said element engages,

and holds said member when the element reaches said position, and a no-voltage magnet for. retaining said element in a holding position.

In witness whereof, I have hereunto set my hand this 18th dayof May, 1907.

-PAUL H. ZIMMER. Witnesses:

,BENJAMIN B. HULL,

HELEN OR'roRn. 

